Share Email Print
cover

Proceedings Paper

Monitoring transient elastic energy storage within the rotary motors of single FoF1-ATP synthase by DCO-ALEX FRET
Author(s): Stefan Ernst; Monika G. Düser; Nawid Zarrabi; Michael Börsch
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The enzyme FoF1-ATP synthase provides the 'chemical energy currency' adenosine triphosphate (ATP) for living cells. Catalysis is driven by mechanochemical coupling of subunit rotation within the enzyme with conformational changes in the three ATP binding sites. Proton translocation through the membrane-bound Fo part of ATP synthase powers a 10-step rotary motion of the ring of c subunits. This rotation is transmitted to the γ and ε subunits of the F1 part. Because γ and ε subunits rotate in 120° steps, we aim to unravel this symmetry mismatch by real time monitoring subunit rotation using single-molecule Förster resonance energy transfer (FRET). One fluorophore is attached specifically to the F1 motor, another one to the Fo motor of the liposome-reconstituted enzyme. Photophysical artifacts due to spectral fluctuations of the single fluorophores are minimized by a previously developed duty cycle-optimized alternating laser excitation scheme (DCO-ALEX). We report the detection of reversible elastic deformations between the rotor parts of Fo and F1 and estimate the maximum angular displacement during the load-free rotation using Monte Carlo simulations.

Paper Details

Date Published: 9 February 2012
PDF: 14 pages
Proc. SPIE 8226, Multiphoton Microscopy in the Biomedical Sciences XII, 82260I (9 February 2012); doi: 10.1117/12.907086
Show Author Affiliations
Stefan Ernst, Univ. Stuttgart (Germany)
Jena Univ. Hospital (Germany)
Monika G. Düser, Univ. Stuttgart (Germany)
Nawid Zarrabi, Univ. Stuttgart (Germany)
Michael Börsch, Univ. Stuttgart (Germany)
Jena Univ. Hospital (Germany)


Published in SPIE Proceedings Vol. 8226:
Multiphoton Microscopy in the Biomedical Sciences XII
Karsten König, Editor(s)

© SPIE. Terms of Use
Back to Top